<?php
/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2018/9/28
 * Time: 19:02
 */
include "config.php";

$uname=isset($_REQUEST["unameA"])?$_REQUEST["unameA"]:"";
$sqlExistuser="SELECT * FROM userinfo WHERE u_name=?;";
$stmt=$connection->prepare($sqlExistuser);
$stmt->bind_param("s",$uname);
$stmt->execute();
$result=$stmt->get_result();
if($result->num_rows>=1){
    print_r("false");
}
else{
    print_r("true");
}
$stmt->close();
$connection->close();